An Astrophysicist's Top 10 Unsolved Mysteries

There are a lot of unknowns in space but here are my top 10 unanswered questions. Go to http://brilliant.org/DrBecky and sign up for free. The first 200 people that go to that link will get 20% off the annual premium subscription.

Here's my top 10 in no particular order, let me know in the comments if you think I've missed anything!

1. What’s inside a black hole?
2. What’s the Universe expanding into?
3. What is dark energy?
4. What’s dark matter made of?
5. Where is all the antimatter?
6. What happened in the first 10^-43 seconds of the Universe?
7. What came first: the galaxy or the black hole?
8. What causes fast radio bursts?
9. Why does the Sun’s magnetic field flip?
10. Does life exist on other planets?

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